// UUID
var uuidChars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".split("");
function uuid() {
	var r;
	var uuid = [];
	uuid[8] = uuid[13] = uuid[18] = uuid[23] = "-";
	uuid[14] = "4";
	
	for (i = 0; i < 36; i++) {
		if (!uuid[i]) {
			r = 0 | Math.random() * 16;
			uuid[i] = uuidChars[(i == 19) ? (r & 0x3) | 0x8 : r];
		}
	}
	return uuid.join("");
}